From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:46674 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932256AbeEHINs (ORCPT ); Tue, 8 May 2018 04:13:48 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mayank Rana , Jack Pham , Felipe Balbi Subject: [PATCH 4.16 37/52] usb: dwc3: gadget: Fix list_del corruption in dwc3_ep_dequeue Date: Tue, 8 May 2018 10:10:35 +0200 Message-Id: <20180508073933.303811611@linuxfoundation.org> In-Reply-To: <20180508073928.058320984@linuxfoundation.org> References: <20180508073928.058320984@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mayank Rana commit 96bd39df29c29d348d65311e5954c0b7d3a2a790 upstream. dwc3_ep_dequeue() waits for completion of End Transfer command using wait_event_lock_irq(), which will release the dwc3->lock while waiting and reacquire after completion. This allows a potential race condition with ep_disable() which also removes all requests from started_list and pending_list. The check for NULL r->trb should catch this but currently it exits to the wrong 'out1' label which calls dwc3_gadget_giveback(). Since its list entry was already removed, if CONFIG_DEBUG_LIST is enabled a 'list_del corruption' bug is thrown since its next/prev pointers are already LIST_POISON1/2. If r->trb is NULL it should simply exit to 'out0'. Fixes: cf3113d893d4 ("usb: dwc3: gadget: properly increment dequeue pointer on ep_dequeue") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Mayank Rana Signed-off-by: Jack Pham Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/gadget.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1424,7 +1424,7 @@ static int dwc3_gadget_ep_dequeue(struct dwc->lock); if (!r->trb) - goto out1; + goto out0; if (r->num_pending_sgs) { struct dwc3_trb *trb;